We have developed concepts for improving the efficiency of hydrolytic-aspiration type mechanical thrombectomy device (MTD) catheter systems for use in the treatment of thrombosed Hemodialysis Grafts (HDG). These improved systems are capable of providing higher shear-rates for thrombus maceration, with increased clot-aspiration potential and minimal potential for wall damage and distal embolization. The specific aim of this R&D project is to develop working prototypes of the catheter in order to validate all the design concepts and set the stage for further investments necessary to take the device into practical percutaneous thrombectomy use in the treatment of thrombosed HDG. In the first stage, we will extensively test the ability of the prototypes to generate high shear-rates and adequate aspiration potential under physiologic flow conditions with increased emboli-removal rates and reduced distal embolization. Successful development of proof-of-concept design prototypes will lead us to attempt to attract further funding for the in vivo trials needed to take the design into the HDG vascular surgery market.